function convert(num) {
    let nums = [1000, 900, 500, 400, 100, 90, 50, 40, 10, 9, 5, 4, 1];
    let romans = ["M", "CM", "D", "Cd", "C", "XC", "L", "XL", "X", "IX", "V", "IV", "I"];
    let str = '';
    nums.forEach(function (item, index, array) {
        while (num >= item) {
            str += romans[index];
            num -= item;
        }
    });

    return str;
}

console.log(convert(36));
